Corrosion protective lacquer lacquer for braking surfaces of brake disks and/or brake drums, corrosion protective coating produced therefrom, and a method for removing the corrosion protective coating

ABSTRACT

A corrosion protective lacquer is for producing a corrosion protective coating, and a method is for removing the corrosion protective coating. For a more favorable removal, while maintaining simultaneous corrosion protection, the corrosion protective lacquer, and thus also the corrosion protective coating produced from it, includes protective substances that react with oxygen. The corrosion protective coating is abraded by the abrasive effect of the brake linings during braking, the protective substances of the corrosion protective coating being rubbed into the braking surface.

FIELD OF THE INVENTION

[0001] The present invention relates to a corrosion protective lacquerfor braking surfaces of brake disks and/or brake drums, a corrosionprotective coating made thereof, and a method for removing the corrosionprotective coating as it is used in the shop of the applicant.

BACKGROUND INFORMATION

[0002] For protection from corrosion, a brake disk and/or brake drum isgenerally lacquered. For this a lacquer is used which can be removed bybraking, that is, removed by the abrasive action of the brake pad in thearea of the braking surface. This solution has proven particularlyfavorable in vehicles designated for overseas transportation and withreplacement brake disks or drums.

[0003] Despite the advantages of convention methods, braking surfaces ofbrake disks or braking surfaces treated with it still demonstratesensitivities during transportation, especially because of theaggressive salt air during overseas transportation. High qualityassurance costs and partial reworks are connected with this.

[0004] It is an object of the present invention to provide a corrosionprotective lacquer with which a corrosion protective coating may beproduced which makes possible a corrosion protection even in overseastransportation, less rework and cost reduction, and which may be removedas simply as possible.

SUMMARY

[0005] The above and other beneficial objects of the present inventionare achieved by providing a corrosion protective lacquer, a corrosionprotective coating and a method as described herein. Access of oxygen tothe braking surface is prevented by covering at least the brakingsurfaces with a corrosion protective lacquer according to the presentinvention having a high proportion of protective substances that reactwith oxygen.

[0006] In order to achieve the desired effect, a protective substanceproportion of at least 30% by volume, for example, at least 50% byvolume or at least 70% by volume, is practical in the lacquer orclearcoat that is otherwise, for example, of customary type.

[0007] These protective substances may include, for example,non-alkaline and non-earth alkaline metals such as, for example, zinc,elemental aluminum or their oxidizable compounds, such as, for example,FeO. Additionally, phosphorus and/or phosphates are also suitable.

[0008] During removal by braking, the substances are, at leastpartially, for example, pressed and/or rubbed into the surface of thebraking surface, where they remain and further effect protection of themetallic surface from oxidation. This removal by braking may beperformed at any time, for example, however, before delivery of anautomobile to a customer, such as on a roller test stand. Because oneobtains corrosion protective action even after the removal of thecorrosion protective coating by braking, the removal of the corrosionprotective coating may be performed, for example, before mounting thebrake disk, shortly after its manufacture, so that only a brake disk ismounted that is ready and protected from corrosion.

[0009] By the introduction of the protective substances into the surfacerough spots, pores and score marks of the braking surface, the normalsurface roughness of the braking surfaces, which results due to thenatural pores of the brake disk material and/or grinding or turningscore marks, is reduced at the same time. The result is a lesser depthof corrosion, whereby in turn the probability of brake judder islessened at the same time.

[0010] In order to achieve a particularly satisfactory result, theaverage particle size of the protective substances may be smaller thanthe maximum roughness and/or the average pore width and/or the averagescore mark size of the braking surface.

[0011] A metal lacquer having a zinc dust proportion of approximately80% by volume may be a cost-effective solution.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012]FIG. 1 is a cross-sectional view of a brake disk having a combinedbrake drum and a corrosion protective lacquer applied thereto.

[0013]FIG. 2 is a cross-sectional view of the brake disk illustrated inFIG. 1 having the corrosion protective lacquer solidified to a corrosionprotective coating.

[0014]FIG. 3 is a magnified view of a braking surface after removal ofthe corrosion protective coating.

DETAILED DESCRIPTION

[0015]FIG. 1 is a cross-sectional view of a brake disk 1 having acombined brake drum. The whole surface of brake disk 1 is provided witha corrosion protective lacquer 4. Since the corrosion protective lacquermay be identical to a conventional lacquer except for protectivesubstances 10 (illustrated as individual dots), it is possible to applyit to the surface of brake disk 1 using a normal spraying and/or dippingmethod.

[0016] After application, corrosion protective lacquer 4 is dried orallowed to set or cured into corrosion protective coating 6 (see FIG.2). Since during curing of the corrosion protective lacquer the solvent,for example, water, escapes from coating 6, the proportion of theprotective substances 10 in corrosion protective coating 6 increases ascompared to their proportion in corrosion protective lacquer 4. Asillustrated in FIG. 2, this may be seen in the greater density of thepoints and coating 6.

[0017] Due to the high proportion of protective substances 10 of, forexample, more than 70% by volume, even a deep crack may not endangerbraking surface 2 of the brake disk and/or braking surface 3 of thebrake drum through corrosion, since the oxygen is intercepted byprotective substances 10, whereby they themselves react in the form ofan oxidation.

[0018]FIG. 3 is a magnified view of braking surface 2, 3 after removalof corrosion protective layer 6 by braking. It may be seen thatprotective substances 10 have been inserted into pores 7 and score marks8 or other recesses 9.

[0019] This arrangement reduces the normal roughness of braking surface2 and, along with that, the corrosion depth to be expected. Furthermore,at least initially, the rust attack in a vehicle standing still for along time is reduced, since in this case, corrosion protection byself-oxidation of protective substances 10 remains in effect. That is,the inserted protective substances 10 act as a sacrificial anode.

What is claimed is:
 1. A corrosion protective lacquer for producing acorrosion protective coating for a braking surface of at least one of abrake disk and a brake drum, comprising: a protective substanceconfigured to react with oxygen.
 2. The corrosion protective lacqueraccording to claim 1, wherein the protective substance includes at leastone of a non-alkaline metal, a non-earth alkaline metal, an oxidizablemetal combination, phosphate and phosphorous.
 3. The corrosionprotective lacquer according to claim 1, wherein the protectivesubstance includes at least one of zinc, an oxidizable iron oxide, FeO,at least mostly elemental aluminum and at least mostly elementalaluminum in powder form.
 4. The corrosion protective lacquer accordingto claim 1, wherein the protective substance is in a proportion of atleast 30% by volume.
 5. The corrosion protective lacquer according toclaim 1, wherein the protective substance is in a proportion of at least50% by volume.
 6. The corrosion protective lacquer according to claim 1,wherein the protective substance is in a proportion of at least 70% byvolume.
 7. The corrosion protective lacquer according to claim 1,wherein a starting material of the corrosion protective lacquer includesone of a normal clear lacquer and a tinted lacquer.
 8. The corrosionprotective lacquer according to claim 1, wherein a starting material ofthe corrosion protective lacquer includes a low proportion of an organicsolvent.
 9. The corrosion protective lacquer according to claim 8,wherein the corrosion protective lacquer includes a water-based lacquer.10. The corrosion protective lacquer according to claim 1, wherein theprotective substance has an average grain size that is substantiallyequal to at least one of a maximum roughness and an average score marksize of the braking surface.
 11. A corrosion protective coating for abraking surface of at least one of a brake disk and a brake drum,comprising: a lacquer including a protective substance that reacts withoxygen.
 12. The corrosion protective coating according to claim 11,wherein the protective substance includes at least one of a non-alkalinemetal, a non-earth alkaline metal, an oxidizable metal compound,phosphate and phosphorous.
 13. The corrosion protective coatingaccording to claim 11, wherein the protective substance includes atleast one of zinc, oxidizable iron oxide, FeO, at least mostly elementalaluminum and at least mostly elemental aluminum in powder form.
 14. Thecorrosion protective coating according to claim 11, wherein theprotective substance in the corrosion protective coating has aproportion of at least 30% by volume.
 15. The corrosion protectivecoating according to claim 11, wherein the protective substance in thecorrosion protective coating has a proportion of at least 50% by volume.16. The corrosion protective coating according to claim 11, wherein theprotective substance in the corrosion protective coating has aproportion of at least 70% by volume.
 17. The corrosion protectivecoating according to claim 11, wherein the protective substance has anaverage grain size substantially equal to at least one of a maximumroughness, an average pore diameter and an average score mark size ofthe braking surface.
 18. A method for removing a corrosion protectivecoating from a braking surface of at least one of a brake disk and abrake drum, comprising the steps of: adding a protective substance to acorrosion protective lacquer, the protective substance being configuredto at least one of chemically react with oxygen in response to contactwith oxygen and bind with oxygen in response to contact with oxygen;applying the corrosion protective lacquer to the braking surface afterthe adding step; converting the corrosion protective lacquer to form thecorrosion protective coating; and abrading the corrosion protectivecoating by an abrasive effect of a brake lining during braking, theabrading step including the substep of rubbing the protective substanceinto the braking surface.
 19. The method according to claim 18, whereinthe converting step includes the substep of hardening the corrosionprotective lacquer.
 20. The method according to claim 18, wherein therubbing substep includes the substep of rubbing the protective substanceinto at least one of recesses, rough areas, pores and grooves of afriction surface of the brake disk.
 21. The method according to claim18, wherein the protective substance includes at least one of anon-alkaline metal, a non-earth alkaline metal, an oxidizable metalcompound, phosphate and phosphorous.
 22. The method according to claim18, wherein the protective substance has an average grain sizesubstantially equal to at least one of a maximum roughness, an averagepore diameter and an average score mark size of the braking surface. 23.The method according to claim 18, further comprising the step ofdelivering the brake disk to a customer after the abrading step.
 24. Themethod according to claim 18, further comprising the step of equipping avehicle with the brake disk after the abrading step.
 25. The methodaccording to claim 18, further comprising the step of mounting the atleast one of a brake disk and a brake drum on a vehicle before theabrading step.
 26. The method according to claim 18, further comprisingthe step of mounting the at least one of a brake disk and a brake drumon a vehicle after the abrading step.